Authors(s) and Affiliation(s)

Abstract

Mountain-top detritus characterizes the 2 high summits of the Gaspésie Montains, eastern Canada. It is suggested that these angular rock-rubble accumulations developed from the disintegration of coarse-grained igneous bedrock exposed to thermal stress and ice segregation during prolonged episodes of permafrost formation in the cold periods of the Pleistocene. Frost wedging and frost heaving ("jacking") were the primary mechanisms. Today, climatic conditions on the summits permit only thin and marginal permafrost bodies. Stonenets and stripes are developed where a residual bedrock-derived debris mantle is present. They reflect frost-induced movements within the active layer. The latest of these movements probably occurred during the cold period following the LGM and persisted into the mid-Holocene. The transition from nets to stripes relates to slope angle